Wireless communication systems are widely used to provide voice and data services for multiple users using a variety of access terminals such as cellular telephones, laptop computers and various multimedia devices. Such communications systems can encompass local area networks, such as IEEE 801.11 networks, cellular telephone and/or mobile broadband networks. The communication system can use one or more multiple access techniques, such as Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA) and others. Mobile broadband networks can conform to a number of system types or partnerships such as, General Packet Radio Service (GPRS), 3rd-Generation standards (3G), Worldwide Interoperability for Microwave Access (WiMAX), Universal Mobile Telecommunications System (UMTS), the 3rd Generation Partnership Project (3GPP), Evolution-Data Optimized EV-DO, or Long Term Evolution (LTE).
Some systems, such as LTE, strive to serve densely populated areas with very high data rates. One way in which an LTE network can provide dense coverage and high data capacity in a cost effective manner is to utilize Relay nodes (RNs), which function as base stations to user devices, but do not have a backhaul connections as base stations do. Instead, the RN communicates with an LTE base station (eNB) via a standard LTE radio link. BS is also be commonly referred to as evolved nodeB (eNB), base transceiver station, controller, access point (AP), access network (AN), and so forth, while a user device or user equipment (UE) may also be commonly referred to as mobile station (MS), access terminal (AT), subscribers, subscriber stations, terminals, mobile stations, and so on.
The use of RN, while increasing data rate, may decrease the throughput (data rate per time slot) because of the sharing of the channel resources between the RN, the eNB, and the user devices. One of the challenges in incorporating relay nodes therefore involves the maximization of spectral efficiency.